Chemical formula: _Na2S

Chemical name: sodium sulfide, Sodium Sulfur, Disodium sulfide

Origin: China

Specification: 25 kg/bag

Physical properties: red or yellow flakes, rotten egg smell.

Chemical properties:

In industry Na2S is produced by carbothermic reduction of sodium sulfate and usually using coal:

Na2SO4 + 2 C → Na2S + 2 CO2
In the laboratory, Na2S can be prepared by reducing sulfur with sodium in anhydrous ammonia. Alternatively, sulfur can be reduced by sodium in dry THF with a catalytic amount of naphthalene:

2 Na + S → Na2S
Sodium sulfide can also be produced by reacting sodium cyanide and sulfuric acid, however this reaction is very toxic as hydrogen cyanide is formed in the process.

Reaction with inorganic reagents
The dissolution process can be described as follows:

S-2 + H2O → HS- + OH-
Sodium sulfide can be oxidized when heated with sodium carbonate and sulfur dioxide:

2 Na2S + 3 O2 + 2 CO2 → 2 Na2CO3 + 2 SO2
Oxidation with hydrogen peroxide gives sodium sulfate:

Na2S + 4 H2O2 → 4 H2O + Na2SO4
After treatment with sulfur, polysulfides are formed:

2 Na2S + S8 → 2 Na2S5